WASHINGTON - The US today approved sale of USD 952 million worth of attack helicopters, missiles and other defence equipment to Pakistan to help the country with its counter-terrorism operations, but said the deal would "not alter" the military balance in the region.

Notification for the proposed sale of the AH-1Z Viper Attack Helicopters and AGM-114R Hellfire II Missiles and associated equipment, training and logistical support has been sent by Defence Security Cooperation Agency to Congress.

"This proposed sale of helicopters and weapon systems will provide Pakistan with military capabilities in support of its counter-terrorism and counter-insurgency operations in South Asia," the agency said in a statement.

The agency, however, said that the sale of the equipment and support will "not alter the basic military balance in the region."

The deal would also contribute to the "foreign policy and national security of the United States by helping to improve the security of a country vital to US foreign policy and national security goals in South Asia."

The proposed sale includes a "precision strike, enhanced survivability aircraft" that Pakistan can operate at high-altitudes.

"By acquiring this capability, Pakistan will enhance its ability to conduct operations in North Waziristan Agency, the Federally Administered Tribal Areas, and other remote and mountainous areas in all-weather, day-and-night environments," it said.

Pakistan has been hit by a rising wave of sectarian violence in recent years, most of it carried out by militant Sunni groups targeting Shias.

And the country's volatile northwest has been fiercely battling homegrown Taliban insurgency that was revived in 2004. The country's army have been engaged in a full-scale offensive against the militants since last year.

In December, Taliban gunmen killed 154 people, most of them students, in an attack on an army-run school in Peshawar.

The proposed sale of defence equipment by the US is to be implemented over a period of five and a half years, involving technical support, training by American personnel.